Many changes in body composition, including gain in fat mass and loss of lean muscle mass, are observed as the body ages. This affects physical ability in the elderly. It is important to have a good understanding of whether or not these two changes in the body are associated with physical disability.

To establish a correlation between body composition and physical ability, Ms. Bouchard and her colleagues measured the fat mass and lean mass of 904 subjects. The subjects also underwent five different tests of physical ability, including walking speed and balance.

The results showed that fat mass, and not lean mass, is associated with physical ability in the elderly. In order to limit physical disability, the first goal should therefore be to reduce fat mass, rather than to try to increase lean mass.

This research project was the starting point for Ms. Bouchard's doctoral research on the association between obesity and physical ability in the elderly. As of autumn 2008, Ms. Bouchard is completing her doctoral thesis. She will begin a postdoctoral fellowship in January 2009.